Safety-stop for elevators



A. OPRISAK AND J. PROKOPOWICZI SAFETY STOP FOR ELEVATORS.

APPLICATION FILED FB.26,1919.

1,391,575, PatentedSept. 20,1921.

2 SHEETSSHEET l.

Andrew Elpm'saK I an 2% John Prnknpuwmz mw Momm I A. OPRISAK AND J.PROKOPOWICZ.

SAFETY STOP FOR ELEVATORS.

' APPLICATKON FILED rmze, 1919.

PatntedSept. 20,1921.

2 SHEETSSHEET 2;

7 Mm Z M, M y W fly NIH- AM 7 M 0 1 w? 7 E... p Wm I J 5. i mx A z V r w6 M Andrew Elpria J uhn P R P UNITED- STATES ANDREW OPRIS.AK AND JOHNPROKOPOWICZ, OF DETROIT, MICHIGAN.

SAFETY-STOP FOR ELEVATORS.

Application filed February 26, 1 919.

To all whom it may concern:

Be it known that we, ANDREW OPRISAK and JOHN PnoKoPowIoz, citizens ofAustria and Poland, respectively, and residents. of Detroit, in thecounty of WVayne and State of Michigan, have invented certain new anduseful Improvements in Safety-Stops for Elevators, of which thefollowing is a specification.

This invention relates; to a stop mechanism adapted for application toelevatorssuch as are used in mines, factories, and buildings, and anobject of the invention is to provide a safety stop for elevators whichwill automatically arrest the movement of the elevator in case theoperatingrope or mechanism breaks or becomes inoperative, preventing thedropping of the elevator cage and consequently preventing serious injuryto persons in the elevator or mutilation of the elevator itself.

Morespecifically, the object of the invention is to provide toothedstandards at each side of the elevator cage, which are adapted to beengaged by locking pawls pivotally carried by the elevator cage andnormally held in inoperative position, but which are moved intooperative positions upon a sudden dropping of the elevator cage forengagement with the vertical racks to arrest falling movement of theelevator.

Other objects of the invention will appear in the following detaileddescription taken in connection with the accompanying drawings, forminga part of this specifica tion and in which drawings:

Figure 1 is a fragmentary side elevation of an elevator cage showing theimproved safety stop mechanism applied thereto.

Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1.

Fig. 3 is a fragmentary side elevation of an elevator cage showing thestop applied thereto, the said stop mechanism being in a movementarresting position of the elevator cage while one of the racks is shownin section. 7

Fig. 4 is a fragmentary view similar to Fig. 3, only showing the lockingpawls in their normal or inoperative position.

Referring more particularly to the drawings, wherein like charactersindicate like and corresponding parts throughout the several views, 1indicates an elevator cage of any ordinary type, which is guided, in itsvertical movement by the engagement of Specification of Letters Patent.

Patented Sept. 20, 1921.

Serial No. 279,469.

the recesses in the end of the top bar 2 over the vertical guiding rails3. In the drawings, the elevator cage 1 is operated by a suitable cable4 which is connected to a link 5. The link 5 extends slidably throughthe top bar 2 and extends through a lower bar 6, being connected to thesaid bar; thus during the proper or ordinary movement of the elevator,the bar .6 will be moved upwardly toward the top cross bar 2, beinglimited in its upward movement by suitable stops 7 which are carried bythe upper cross bar 2. Suitable guiding rods 8 are carried by the topcross bar 2 and extend slidably through the lower bar 6. Spiral springs9 are coiled about the guide pins 8 and have their upper ends engagingagainst the undersurface of the upper cross bar 2, while their lowerends engage the upper surface of the lower. cross bar 6, the saidsprings tending to expand and force the lower bar 6 away from the upperbar 2.

Vertical rack bars 10 and 11 are positioned upon opposite sides of theelevator 'cage'l, being attached, in any suitable manner, to the guiderails 3, and these rack bars have teeth 12 upon each of their sideswhichare adapted tobe engaged by the teeth of pawls 13, 14, 15 and 16 toarrest downward movement of the elevator cage. The pawls Band 14, a pairof each of which are provided are pivotally carried by suitable pins 17at the upper ends of the elevator cage and each of the pawls 13 isconnected by a bar, 18 to the respective pawl of the lower pair 15 tooperate them synchronously to move their toothed inner edges intoengagement with the teeth 12 of the rack bar 10 to arrest the downwardmovement of the elevator. Each of the pawls 14 is connected by means ofa bar 19 to the corresponding pawl 16 of the lower pair of pawls. Theselower pairs of pawls 15 and 16 are pivotally mounted upon suitable pins19 and 20, carried by blocks 21. The blocks 21 are attached in anysuitable manner beneath the bottom of the elevator cage 1. Contractilesprings 22 are connected to each of the pawls and to a part of theelevator cage for quickly snapping the pawls into locking engagementwith the rack teeth 12 should the elevator cable 4 break or anycontrolling part of the elevator mechanism become inoperative, causing aslacking of the cable 4.

Yokes 24 and 2,5 are connected to the upper cross bar 6 and they havethe upper ends of their arms angled to provide outwardly extending arms26 which engageover the upper cross pieces 27 of the elevator cagestructure. The arms 26 have eyes 28 formed upon their free ends to whichlinks 29 are connected. The links 29 which are connected to the arms 26of the yokes 24 are connected to the upper pair of pawls 13 while thelinks 29 which are connected to the arms 26 of the yokes 25 areconnected to the upper pair of pawls 14. In case the cable 4 breaks orany controlling part of the elevator mechanism becomes inoperative, soas 'to release the supporting action of the'cable 4, the springs 9 willact to move the bars '6 downwardly which'will, through the connectionofthe yokes 24 and 25'and links 29 rock the upper pairs of pawls 13 and'14; and consequently rock the lower pairs of pawls 15 and16 through themedium-of the'arms' orbars 18 and 19, to cause the teeth of the pawls toengage the teeth of the racks 10 and 11 and arrest downward movement ofthe elevator cage.

Changes in details may be made without departing fromthe spirit of thisinvention, but;

We claim 1.' In a safety stop for elevators, the combination, with anelevator cage, and the supporting means therefor, of a bar movablycarried by the elevator cage and normally held in upward position bysaid supporting means, spring means for forcing said bar downwardly withrespect to the cage, yokes carried by the bar adapted for engagementwith the cage to limit the action of the spring means upon release ofthe supportin means, racks, pawls pivotally carried by the elevatorcage, and means connecting said yokes and pawls to force the pawls intoengagement with the racks upon release of the supporting means. i 7

2. In a safety stop for elevators, the combination, with an elevatorcage, and the supporting means therefor, of a bar movably means, saidoutwardly extending arm provided with an aperture therein, racks, pawlspivotally carried by theelevator cage, and

links pivotally connected to the apertures of said yokes and connectedat their other ends to the pawls, for the purpose of forcing thepawlsinto engagement withthe racks upon release of the supporting means.

3. In a safety stop for elevators, the combination with an elevator cageand the supportin means therefor, carried held in upward position bysaid supporting means, racks adjacent said elevator cage,

of a bar 'movably pawls pivotally carried by said elevator cage,

means connecting said movable bar and said pivoted pawls for normallyholding said pivoted pawls out ofengagement with said racks wh'ensaidmovable bar is held in upward position by said supporting means,

and springs for each of said pawls, directly by the elevator cage andnormally connecting said pawls to'said elevator cage for action to forcesaid pawls into engagement with said rack upon release of saidsupporting means.

ANDREW OPRISAK. JOHN PROKOPOWICZ.

